Evaluation of cardiovascular risk predicted by different SCORE equations: the Netherlands as an example.

Background: In Europe, for primary prevention of cardiovascular diseases (CVD), the Systematic COronary Risk Evaluation (SCORE) risk charts for high-risk and low-risk regions (SCORE-high and SCORE-low, respectively) are used. For the Dutch 'Clinical Practice Guideline for Cardiovascular Risk Management' an adapted SCORE risk chart (SCORE-NL) was developed in collaboration with the SCORE group. We evaluated these three SCORE equations using Dutch risk factor and mortality data.
Design: Prospective cohort study with 10-year follow-up.
Methods: Baseline data were collected between 1987 and 1997 in 32 885 persons aged 37.5-62.5 years. Vital status was checked and causes of death were obtained from Statistics Netherlands. On the basis of the level of risk factors, the expected number of CVD deaths was calculated by applying the three SCORE equations and compared with the observed number.
Results: The observed CVD mortality was three-fold higher in men (n=242; 1.6%) than in women (n=83; 0.5%). On the basis of SCORE-NL, 8.5% of the men and 0.8% of the women had a CVD mortality risk of 5% or more. The ratio of the observed-to-expected number of CVD deaths was 0.75 for men and 0.55 for women using SCORE-NL, 0.54 and 0.56 using SCORE-high, and 1.11 and 0.95 using SCORE-low.
Conclusion: At the population level, SCORE-low predicts the number of CVD deaths well, whereas both SCORE-NL and SCORE-high overestimate the number of CVD deaths by a factor 1.5-2.